Do HR check a candidate's Facebook page or Twitter account before contacting them?

I had heard of an Urban Legend where the HR team had checked a candidate's Facebook the night before the interview for a job.
The candidate had updated his/her status around 3 am in the morning along the lines of : 'Can't get the stupid toaster to work!' and this cost him the job.
I think Facebook and Twitter, for a lot of people, are a very personal platform used to share random details with their friends.
This also brings in the debate of the on-screen and off-screen personas of people.
Judging people through their Facebook or Twitter posts is a highly superficial way of trying to understand someone.
I know some of the smartest academicians in world class universities whose Facebook pages are in my opinion very boring as compared to what they are offline as real people.
Then again, if the HR team is so curious about the candidate, contact their Referees ( which they always ask us for in the job form but I wonder if they ever do) or check their LinkedIn page.

Companies need to realize that they are not entitled  to know everything about a candidate's life.

"Candidate's personal life should never be a concern of their employer/potential employer " I strongly agree.

We recruit through linkedin, so that is a profile we would review.
We cannot even look at twitter, as this is blocked by the company.
Next to that I agree that I am interested in the professional profile of an individul, not her holiday pictures.
hwat they do in their spare time is largely up to them, as long as it does not interfere with theocmpany.
One has to ask, what would I do with such information, in a time and age where in many countries it is forbidden to post a picture on a CV, I should seriously look at their private pictures.
That is not only highly unprofessional, it is making companies potentially liable if it came out.

I hear some companies check candidate's Facebook page or Tweets (If they could) to see and analyze first impression personalities.
This could be very risky..

I do agree, checking LinkedIn & Facebook profile give us the first impression related to the culture & professionalism of the candidate.
Not to mention that you can also look for a connection in common through linkedIn to ask for feedback related to the potential candidate.

I think it makes no sense.
Professionalism and personal life are two different things.
Companies cant find positive things (Professional) from Facebook and twitter.
LinkedIn is fine because that is a professional site but there is absolutely no reason to check anyone’s Facebook page (unless they are a current employee and the HR find out they have been slandering or spreading company confidential secrets).

facebook page and twitter account of personal matters candidate ..and inform HR due to the approval of the candidate himself might agree may refuse

Since social Media reflects a lot about a person nowadays, you call tell what kind of person and what character you would be dealing with just by viewing S.M.
profiles (if they were public).
Out of my experience in recruitment and with other recruiters, i realized that a lot of HR people do check candidates' social media profiles to know what to expect; this is why a lot of institutions are giving courses and workshops on How to Brand Self on social Media and how to use social media correctly and how much social media affects your personal brand.

It would be better for HR to check the LinkedIn profile before contacting Candidates , because LinkedIn is the Network of professionals and HR can get Idea that either candidate is suitable for the Position or not.

Being a recruiter, I regularly check potential candidates profile at LinkedIn as it helps me to have an insight on them. I do often check the Twitter profile but never go for Facebook, as it is something personal. Well, at LinkedIn its good and exhibit individual career profile.